#app2{

}
#app2 .tab-bar{
display: flex;
}
#app2 .tab-bar>li{
border: 1px solid grey;
width: 50%;
}
#app2 .tab-bar > li.selected{
background: yellow;
color: white;
}
#app2 .tab-content{

}
#app2 .tab-content>li{
    display: none;
}
#app2 .tab-content > li.active{
display: block;
}